As curious as it is that so much incorrect science has been and still is being used in the scientific, medical and bioethics literature to argue that fetal "personhood" does not arrive until some arbitrary biological marker event during human embryological development, we are now beginning to experience the "new wave" consequences of passively allowing such incorrect "new age" science to be published and eventually accepted by professionals and non-professionals alike. Once these scientifically erroneous claims, and the erroneous philosophical and theological concepts they engender, are successfully imbedded in these bodies of literature and in our collective consciousnesses, the next logical step is to imbed them in our text books, reference materials and federal regulations.
Such is the case with the latest fifth edition of a human embryology text book by Keith Moore - The Developing Human.1 This text is used in most medical schools and graduate biology departments here, and in many institutions abroad. It will be demonstrated that the contradictory definitions and redefinitions of many of the most basic scientific terms it uses lend scientific credence to the "new age" political agenda of abortion, human embryo and fetal research. In fact this human embryology text book for students actually explicitly engages in abortion counseling - a quite inappropriate use of a basic scientific text book - and uses these incorrectly defined scientific terms to ground and justify its own conclusions about the "scientific correctness" of abortion. What is often not appreciated is that these redefinitions would justify human embryo and fetal research as well.
Of particular concern is Moore's sudden use of the scientifically erroneous term "pre-embryo" in his most recent fifth edition - a fact recently pointed out by Dr. C. Ward Kischer2, a professor of human embryology for over 30 years, who along with others have rejected the scientific validity of this term.3 There has never been any such thing as a "pre-embryo" in human embryology text books until now. Scientifically, fertilization is the beginning of a human being as well as the beginning of a human embryo. The term "pre-embryo" implies that this entity comes before the embryo. This in turn implies that a "pre-embryo" is a "pre-human being". This is scientifically ridiculous.
What is true in the bioethics fetal personhood arguments is true in medical and scientific educational text books. The term "pre-embryo" is based on incorrect science and should not be used. Unfortunately, as Dr. Kischer has also pointed out, the erroneous term "pre-embryo" has also been incorporated in the latest edition of Nomina Embryologica4 - the international nomenclature reference text which certainly will urge medical and human embryology text books world-wide to comply with the inclusion of this erroneous terminology - and presumably with abortion counseling, human embryo and fetal research as well.
There are simply no valid or sound scientific, philosophical or theological bases for the use of the erroneous term "pre-embryo", for its use in arguments on fetal "personhood", or for its inclusion as a legitimate stage of human development in any article, book or text - especially a human embryological text book or official international reference for embryological nomenclature. Nor should this scientifically erroneous term be allowed to be used as a scientific rationale to justify the abortion of a pre-born child, or for his or her use in fetal research. Scientific and ethical reasons would certainly preclude these texts from being used or sanctioned in any Catholic educational or health care institutions or facilities.
It is a given that any scientific text must be updated and changed to keep up with the rapid scientific advancements in basic knowledge. But there is a point past which updating ends, and politicizing begins. I leave it up to the readers to determine if that point has been passed with this text.
An examination and comparison of Moore's third and fifth editions will indicate considerable contradictions and confusion in very basic human embryology terminology. Concomitantly this confusion lends itself to a definite progression in the definitions and uses of several of the most basic scientific terms, terms which will ground the eventual use of the erroneous term "pre-embryo" in his fifth edition. In turn, the use of the term "pre-embryo" in the fifth edition will ground and scientifically justify the abortion counseling which is also inappropriately incorporated in this student text book.
And it will be demonstrated that if Moore's texts were to be referred to by public policy makers in their considerations for the use of "human" subjects in experimental medical research, the present OPRR regulations could be "corrected" to allow for unfettered research on preborn human beings up to the ninth week of embryological development.
Furthermore, the erroneous conceptual precedents being established now in the arguments on "personhood" in the abortion, human embryo and fetal research issues could surely be transferable to certain "classes" of adult human beings, rendering them "non-persons" as well, and therefore arguably prime candidates for their use in basic and medical research as well.
In order to demonstrate these concerns I will first turn to a comparison of these two editions, and trace in particular the confusing etiology of the terms "pre-embryo", "embryo", and "pregnancy".
The term "pre-embryo" has an interesting recent history. It was originally used in bioethics debates on the use of "early human embryos" in experimental medical research. The term was actually implied as far back as 1979 by the Ethics Advisory Board to the United States Department of Health, Education and Welfare: "... the [early] human embryo is entitled to profound respect, but this respect does not necessarily encompass the full legal and moral rights attributed to persons".5 In the 1984 Warnock Committee Report in Great Britain, a similar sentiment was expressed: "The human embryo... is not under the present law of the United Kingdom accorded the same status as a living child or adult, nor do we necessarily wish it to be accorded the same status. Nevertheless, we were agreed that the [early] embryo of the human species ought to have a special status."6 The debate was then taken up in Australia and the term "pre-embryo" was finally rejected by the 1986 Harradine "Human Experimentation Bill".7 It was similarly rejected by several other international commissions, e.g., the 1986 and 1989 reports of the Parliamentary Assembly of the Council of Europe.8
In the United States, the Ethics Committee of the American Fertility Society claimed in its 1986 special report that early events in mammalian development concern, above all, the formation of extraembryonic - rather than embryonic -structures. "This means that the zygote, cleavage and early blastocyst stages should be regarded as preembryonic rather than embryonic."9 This theme, that there is a significant developmental structural (and therefore moral) difference between the "extraembryonic" and the "embryonic" membranes of the early human embryo, was echoed by many members of the Ethics Committee of the American Fertility Society.
For example, Howard Jones, a pioneer in infertility "therapy" and in vitro fertilization (IVF) clinics, argued: "While the embryoblast segregates and is recognizable toward the end of [preimplantation], it consists of only a few cells, which are the rudiment of the subsequent embryo."10 Another member, John Robertson11, uses the same rationale in the legal arena to argue for "brain-birth". He often quotes full pages from the work of yet another member of the Ethics Committee of the American Fertility Society, Clifford Grobstein,12 who is also involved in IVF studies, but whose specialty is amphibian embryology (not human embryology).
Yet another member of the Ethics Committee of the American Fertility Society, Richard McCormick, S.J., in his own arguments about the "moral" status of the human "pre-embryo", quotes from Grobstein's "embryology", as well as from "an unpublished study of a research group of the Catholic Health Association entitled 'The Status and Use of the Human Preembryo'".13 According to Grobstein and McCormick,14 "pre-embryos" are merely "genetic individuals" and not "developmental individuals" yet, and therefore they are not "persons". Since they are not legitimate full-blown "persons" yet, they do not have the moral or legal rights and protections that actual human persons possess (and therefore these "pre-embryos" could be aborted, experimented with, disposed of, etc.).
As noted, the new fifth edition of Keith Moore's The Developing Human incorporates the scientifically erroneous embryological term "pre-embryo" for the first time as a formal legitimate period of human development. For example, in Chapter Two, Moore begins his summary of the first week of human development by stating: "The pre-embryonic period of human development begins at fertilization..." (p. 37). In Chapter Eight Moore states: "in vitro studies of cleaving human zygotes (pre-embryos) less than 5 days old have revealed a high incidence of abnormalities." And in the same chapter he states: "Inactivation of genes on one X chromosome in somatic cells of female pre-embryos occurs at about the time of implantation..."(p. 144).
Perhaps it is worth noting the source on which Moore bases his nomenclature in his fifth edition: "The terminology in this book is based on the third edition of Nomina Embryologica which was published as part of the sixth edition of Nomina Anatomica (Warwick, 1989)".15 Yet a number of writers have argued cogently and vigorously that the science used to ground the term "pre-embryo" is erroneous, and therefore the ethical and legal conclusions about the "personhood" of the early developing human being (based on that erroneous science) are also erroneous. Why would Moore or Nomina Embryologica suddenly use such a controversial term as "pre-embryo" now?
The term simply has no basis in fact, and has been flatly rejected by many other human embryologists who refuse to use the scientifically erroneous term in their own human embryology text books. As Kischer so succinctly noted, human embryologists do not use or acknowledge the term "pre-embryo". For example, O'Rahilly and Muller state quite emphatically in their human embryology text book: "The ill-defined and inaccurate term "pre-embryo" which includes the embryonic disk is said either to end with the appearance of the primitive streak (or in the Nomina Embryologica) to include neurulation. The term is not used in this book"16
(emphasis mine). Kischer also points out that the term is not indexed or used in the most recent edition of Stedman's Medical Dictionary,17 in any of the established human embryology texts - e.g., in Larsen's18 or in Patten's19 texts - nor in the scientific literature on human development. As he notes, there is no such stage in human development as the "pre-embryo", and he cautions that: "Human embryology is now in danger of being rewritten as a stratagem statement of current socio-legal, but also of late, even theological, issues. Unless the errors are corrected now, we will be in danger of entering a protracted period of false concepts concerning our own development".20
In their arguments, Grobstein and McCormick claim that the "pre-embryo" is not a "developmentally single individual" (and therefore not yet a "person") because, for example, in the 5-6 day old blastocyst, all of the cells of the outer trophoblast layer are discarded after birth. Only the cells from the inner embryoblast layer become the later fetus and adult human being.21
Strangely, in both the third and the fifth editions of Moore's texts, such scientific statements about the blastocyst are made by Moore in the early chapters of the texts. But in other later chapters of both texts, Moore bluntly contradicts those scientific statements, and thus in effect contradicts any supposed claims that could be made about "pre-embryo's" and "personhood". These scientific contradictions are confusing. For example, in the early chapters of both texts he states:
During stage 3 of development (about four days), cavities appear inside the compact mass of cells forming the morula, and fluid soon passes into these cavities from the uterine cavity. As the fluid increases, it separates the cells into two parts: (1) an outer cell layer, the trophoblast... which gives rise to part of the placenta, and (2) a group of centrally located cells, known as the inner cell mass (or embryoblast), which gives rise to the embryo. (p. 33; also in summary, p. 37)
[In Figure depicting the cleavage of the zygote and the formation of the blastocyst](p. 34)
NOT MENTIONED
NOT MENTIONED
Shortly after the morula enters the uterus (about four days after fertilization), spaces appear between the central blastomeres of the morula. Fluid soon passes through the zona pellucida into these spaces from the uterine cavity. As the fluid increases, it separates the blastomeres into two parts; (1) a thin outer cell layer (or "mass") called the trophoblast... which gives rise to part of the placenta, and (2) a group of centrally located blastomeres, known as the inner cell mass (or embryoblast), which gives rise to the embryo. (p. 35; also in summary, p. 38)
[In Figure depicting cleavage of the zygote and formation of the blastocyst]: The inner cell mass, or embryoblast, gives rise to the tissues and organs of the embryo. (p. 34)
[formulation of the morula] Compaction permits greater cell-to-cell interaction and is a prerequisite for segregation of the internal cells that form the embryoblast or inner cell mass of the blastocyst. (p. 33)
The strong implication here is that there is a clear separation between the inner and outer cell layers. The cells from the outer trophoblast layer are essentially non-embryonic, and in fact are all discarded after birth as placental membranes, etc. Only those cells from the inner layer, i.e., the embryoblast, actually really ever become or make up the cells, tissues and organs of the later embryo, fetus and adult human being. The philosophical (and theological) implication that Grobstein and McCormick want to draw is that because of this early strict separation and eventual separate and different "ontological" destinations and fates, there is as yet no "developmental" individual present (and therefore no "person"). The "pre-embryo", then, is to be considered as a "pre-person".
However, in Chapter 7 (in both editions), i.e., "The Fetal Membranes and Placenta", Moore contradicts his own earlier scientific statements about the relation between the inner and outer cell layers, and whether or not, in fact, both cell layers intermingle from the beginning, and both in fact are represented later in the embryo, fetus and the adult human being:
During stage 5 of development (7-12 days), as the blastocyst is implanting, early differentiation of the inner cell mass occurs. A flattened layer of cells, the hypoblast (primitive endoderm), appears on the surface of the inner cell mass facing the blastocyst cavity at about seven days... Recent evidence indicates that the hypoblast is probably displaced to extraembryonic regions. (p. 33)
The chorion, the amnion, the yolk sac and the allantois constitute the embryonic or fetal membranes. These membranes develop from the zygote, but do not form parts of the embryo, with the exception of portions of the yolk sac and allantois. The dorsal part of the yolk sac is incorporated into the embryo as the primordium of the primitive gut... The allantois is represented in the adult as a fibrous cord, the median umbilical ligament, which extends from the apex of the urinary bladder to the umbilicus. (p. 111)
At about 7 days, a flattened layer of cells called the hypoblast (primitive endoderm) appears on the surface of the inner cell mass facing the blastocyst cavity... [THERE IS NO DISCUSSION OF ITS DISPLACEMENT] (p. 36)
Cells, probably from the hypoblast, give rise to a layer of loosely arranged tissue, called the extraembryonic mesoderm, around the amnion and primary yolk sac... [footnotes 1,2] The origin of the exocoelomic membrane in the human embryo is thought to be derived from the hypoblast... From studies in the rhesus monkey, there is evidence for the formation of extraembryonic mesoderm from the hypoblast. (p. 42)
The chorion, the amnion, the yolk sac and the allantois constitute the embryonic or fetal membranes. These membranes develop from the zygote but do not form parts of the embryo, with the exception of portions of the yolk sac and allantois. The dorsal part of the yolk sac is incorporated into the embryo as the primordium gut... The allantois is represented in the adult as a fibrous cord, the median umbilical ligament, which extends from the apex of the urinary bladder to the umbilicus. (p. 113)
During stage 5 of development (7-12 days), as the blastocyst is implanting, early differentiation of the inner cell mass occurs. A flattened layer of cells, the hypoblast (primitive endoderm), appears on the surface of the inner cell mass facing the blastocyst cavity at about seven days... Recent evidence indicates that the hypoblast is probably displaced to extraembryonic regions. (p. 33)
The chorion, the amnion, the yolk sac and the allantois constitute the embryonic or fetal membranes. These membranes develop from the zygote, but do not form parts of the embryo, with the exception of portions of the yolk sac and allantois. The dorsal part of the yolk sac is incorporated into the embryo as the primordium of the primitive gut... The allantois is represented in the adult as a fibrous cord, the median umbilical ligament, which extends from the apex of the urinary bladder to the umbilicus. (p. 111)
At about 7 days, a flattened layer of cells called the hypoblast (primitive endoderm) appears on the surface of the inner cell mass facing the blastocyst cavity... [THERE IS NO DISCUSSION OF ITS DISPLACEMENT] (p. 36)
Cells, probably from the hypoblast, give rise to a layer of loosely arranged tissue, called the extraembryonic mesoderm, around the amnion and primary yolk sac... [footnotes 1,2] The origin of the exocoelomic membrane in the human embryo is thought to be derived from the hypoblast... From studies in the rhesus monkey, there is evidence for the formation of extraembryonic mesoderm from the hypoblast. (p. 42)
The chorion, the amnion, the yolk sac and the allantois constitute the embryonic or fetal membranes. These membranes develop from the zygote but do not form parts of the embryo, with the exception of portions of the yolk sac and allantois. The dorsal part of the yolk sac is incorporated into the embryo as the primordium gut... The allantois is represented in the adult as a fibrous cord, the median umbilical ligament, which extends from the apex of the urinary bladder to the umbilicus. (p. 113)
These statements from the later chapters are a clear and direct contradiction of his own statements in the earlier chapters. Moore can't have it both ways. Scientifically and factually, either all of the cells of the trophoblast layer are discarded after birth, or they aren't. Again, some parts of his text imply a black and white separation of the two cell layers; other parts of his text indicate an intrinsic intermingling between the two layers. Scientifically and factually, either there is absolutely no intermingling of the cells of the two layers, or there is. Aside from the confusion these contradictions cause on the purely scientific level, different possible philosophical anthropological conclusions about "personhood" follow from these different and contradictory scientific claims. And different conclusions about ethical and legal rights and protections follow from these contradictory philosophical anthropological definitions of "personhood".
The stakes surrounding these "personhood" arguments are, after all, rather high for preborn human beings. If there is no such thing as an absolute separation; if there is always an intermingling of and communication between the two cell layers; if throughout all of human embryological development the two cell layers and the cells, tissues and organs which are produced from them intermingle; then individuality - both genetic and developmental - is present from fertilization on, and therefore so is "personhood".
On the other hand, if Moore, Grobstein and McCormick are scientifically correct, if there is no continuum of development, and therefore no human "person" yet present in this 5-6 day old human blastocyst (even assuming that the argument is a valid one), what is wrong, then, with using them in destructive experimental basic and medical research? Couldn't one also scientifically and ethically rationalize any type of abortion, including the use of the "morning after" pill, or the French RU486 abortion pill - since what is being aborted is really a "non-person", i.e., a "pre-embryo", or a "pre-human being"?
What is rarely perceived is that the stakes in these "personhood" arguments are just as high for adult human beings as well. Consider that many of the other positions for abortion, human embryo and fetal research argue that these early developing human beings are not persons because they do not exercise "rational attributes"22 (e.g., self-awareness, self-consciousness, awareness of the world around one, etc.) or have advanced levels of "sentience"23 (the ability to feel pain and pleasure). Since empirically we know that the actual exercising of "rational attributes" and the actual capacity for full "sentience" are not present until well after birth24, these same writers have argued for years that infanticide of normal healthy infants and young children is ethically permissible.
But it needs to be appreciated that such "conceptual tools" (i.e. redefinitions of "personhood") would also allow one to conclude logically that certain classes of adult human beings who also do not exercise "rational attributes" or "sentience" would also not be "persons", e.g.: patients with Alzheimer's and Parkinson's diseases, the mentally ill, the mentally retarded, the comatose, drug addicts, alcoholics, stroke victims and paraplegics, etc. If they are not "persons", then they will also not be entitled to ethical or legal protections. Couldn't one also logically argue that these human adults can be terminated or used in experimental medical research - if the "proportionate" need were to arise? (In fact this has actually already taken place in the bioethics literature, where Frey,25 an animal rights activist) argues that human beings with mental illness or mental retardation should be substituted for the higher animal primates in destructive experimental research because those human beings with mental illness or mental retardation are not persons and the higher primate animals are).
These redefinitions of "personhood" are simply politically correct or "new age" criteria used for "quality of life" arguments and decisions. When used within the context of adult medical issues this same concept of "personhood" plays a major role in the debates about cortical brain-death, organ transplantation, the withholding and withdrawal of medical treatments, allocation of scarce medical resources, euthanasia, and any informed consent issues (e.g., living will, informed consent for medical treatment or to take part in experimental or therapeutic medical research, etc.). Whether or not one is politically correct about abortion, human embryo and fetal research, it would seem at least prudent to be aware that these redefinitions of "personhood" could be applied to most of us as well.
Next Page:
Shifting definitions of related scientific terms
1,
2,
3